EFFECT OF STEEL FIBER ON RHEOLOGICAL AND MECHANICAL BEHAVIORS OF HIGH PERFORMANCE SELF-COMPACTING MORTAR

The advantage of self-compacting mortar, when compared to conventional mortar, is its high fluidity and stability in fresh state that allows placing into a form work without the need of vibration. However, self-compacting mortar is developed with the extensive use of additives (e.g superplasticizer) and admixtures (e.g. pozzolan, silica fume, limestone powder, etc). Inadequate mix design will cause separation phenomena to occur in self-compacting mortar that can lead to a drop in compressive strength, and thus high performance self-compacting mortar cannot be achieved. Here, we present a successful mix-proportion design, where the effect of 0.3% and 1% of steel fibers on the rheological and mechanical properties of self-compacting mortar was investigated for w/c 0.3 with and without 10% of silica fume by cement weight. Measurements of slump flow, yield stress and plastic viscosity revealed that incorporation of steel fibers with 0.3% and 1% into w/c 0.3 reduced the slump flow, increased the plastic viscosity, and showed no clear trend for the yield stress. We also show the stability of the mixes visually as photos of aggregates and steel fibers distribution in the fresh mortar and the state of the edge after slump-flow measurement.